feat: Add font hinting support via skrifa

.typos.toml

@@ -16,6 +16,7 @@ SVGinOT = "SVGinOT"
 
 # Match Inside a Word - Case Insensitive
 [default.extend-words]
+wdth = "wdth"
 
 [files]
 # Include .github, .cargo, etc.

crates/resvg/Cargo.toml

@@ -14,6 +14,10 @@ workspace = "../.."
 name = "resvg"
 required-features = ["text", "system-fonts", "memmap-fonts"]
 
+[[example]]
+name = "generate_hinting_comparison"
+required-features = ["text", "hinting"]
+
 [dependencies]
 gif = { version = "0.13", optional = true }
 image-webp = { version = "0.2.0", optional = true }
@@ -42,3 +46,5 @@ memmap-fonts = ["usvg/memmap-fonts"]
 # When disabled, `image` elements with SVG data will still be rendered.
 # Adds around 200KiB to your binary.
 raster-images = ["gif", "image-webp", "dep:zune-jpeg"]
+# Enables font hinting via skrifa (requires `text`).
+hinting = ["usvg/hinting"]

crates/resvg/examples/generate_hinting_comparison.rs

@@ -0,0 +1,78 @@
+//! Run with: cargo run --example generate_hinting_comparison --features text,hinting
+
+use std::sync::Arc;
+use usvg::fontdb;
+
+fn main() {
+    // Load fonts
+    let mut fontdb = fontdb::Database::new();
+    fontdb.load_fonts_dir("crates/resvg/tests/fonts");
+    fontdb.set_sans_serif_family("Noto Sans");
+    let fontdb = Arc::new(fontdb);
+
+    // SVG with small text where hinting is most visible
+    let svg = br#"
+        <svg xmlns="http://www.w3.org/2000/svg" width="400" height="200" style="background: white">
+            <text x="10" y="30" font-family="Noto Sans" font-size="12" text-rendering="optimizeLegibility">
+                The quick brown fox jumps over the lazy dog. (12px)
+            </text>
+            <text x="10" y="60" font-family="Noto Sans" font-size="14" text-rendering="optimizeLegibility">
+                The quick brown fox jumps over the lazy dog. (14px)
+            </text>
+            <text x="10" y="95" font-family="Noto Sans" font-size="16" text-rendering="optimizeLegibility">
+                The quick brown fox jumps over the lazy dog. (16px)
+            </text>
+            <text x="10" y="135" font-family="Noto Sans" font-size="20" text-rendering="optimizeLegibility">
+                The quick brown fox jumps over. (20px)
+            </text>
+            <text x="10" y="180" font-family="Noto Sans" font-size="24" text-rendering="optimizeLegibility">
+                The quick brown fox. (24px)
+            </text>
+        </svg>
+    "#;
+
+    // Render with hinting
+    let opt_hinted = usvg::Options {
+        fontdb: fontdb.clone(),
+        hinting: usvg::HintingOptions {
+            enabled: true,
+            dpi: Some(96.0),
+        },
+        ..usvg::Options::default()
+    };
+
+    let tree = usvg::Tree::from_data(svg, &opt_hinted).unwrap();
+    let size = tree.size().to_int_size();
+    let mut pixmap = tiny_skia::Pixmap::new(size.width(), size.height()).unwrap();
+    pixmap.fill(tiny_skia::Color::WHITE);
+    resvg::render(
+        &tree,
+        tiny_skia::Transform::identity(),
+        &mut pixmap.as_mut(),
+    );
+    pixmap.save_png("hinted.png").unwrap();
+    println!("Saved hinted.png");
+
+    // Render without hinting
+    let opt_unhinted = usvg::Options {
+        fontdb: fontdb.clone(),
+        hinting: usvg::HintingOptions {
+            enabled: false,
+            dpi: Some(96.0),
+        },
+        ..usvg::Options::default()
+    };
+
+    let tree = usvg::Tree::from_data(svg, &opt_unhinted).unwrap();
+    let mut pixmap = tiny_skia::Pixmap::new(size.width(), size.height()).unwrap();
+    pixmap.fill(tiny_skia::Color::WHITE);
+    resvg::render(
+        &tree,
+        tiny_skia::Transform::identity(),
+        &mut pixmap.as_mut(),
+    );
+    pixmap.save_png("unhinted.png").unwrap();
+    println!("Saved unhinted.png");
+
+    println!("Done! Compare hinted.png and unhinted.png");
+}

crates/resvg/src/main.rs

@@ -577,6 +577,8 @@ fn parse_args() -> Result<Args, String> {
         image_href_resolver: usvg::ImageHrefResolver::default(),
         font_resolver: usvg::FontResolver::default(),
         fontdb: Arc::new(fontdb::Database::new()),
+        #[cfg(feature = "text")]
+        hinting: usvg::HintingOptions::default(),
         style_sheet,
     };